package main

import (
	"fmt"
	"io/ioutil"
	"os"
	"os/user"
	"path"

	mastodon "git.gutmet.org/go-mastodon.git"
	goutil "git.gutmet.org/goutil.git/misc"
)

const (
	AppDir           = ".swill" //inside home dir
	fileServer       = "Server"
	fileClientKey    = "ClientKey"
	fileClientSecret = "ClientSecret"
	fileAccessToken  = "AccessToken"
)

type credentials struct {
	server       string
	clientKey    string
	clientSecret string
	accessToken  string
}

func (c *credentials) writeCredentials(appDir string) {
	write := func(file string, s string) {
		optLogFatal("writeToAppDir", ioutil.WriteFile(path.Join(appDir, file), []byte(s), 0640))
	}
	write(fileServer, c.server)
	write(fileClientKey, c.clientKey)
	write(fileClientSecret, c.clientSecret)
	write(fileAccessToken, c.accessToken)
}

func readCredentials(appDir string) *credentials {
	read := func(f string) string {
		s, err := goutil.ReadFile(path.Join(appDir, f))
		optLogFatal("readFromAppDir", err)
		return s
	}
	s := read(fileServer)
	ck := read(fileClientKey)
	cs := read(fileClientSecret)
	at := read(fileAccessToken)
	return &credentials{s, ck, cs, at}
}

func createAppDir(appDir string) {
	ask := func(s string) string {
		a, err := goutil.AskFor(s)
		optLogFatal("createAppDir", err)
		return a
	}
	fmt.Fprintln(os.Stderr, "Did not find "+appDir+", creating.")
	fmt.Fprintln(os.Stderr, "Go to Preferences > Development > New application to register a new app and generate access tokens with read & write permissions")
	err := os.MkdirAll(appDir, 0755)
	optLogFatal("createAppDir", err)
	s := ask("Server URL")
	ck := ask("Client key")
	cs := ask("Client secret")
	at := ask("Access token")
	c := credentials{s, ck, cs, at}
	c.writeCredentials(appDir)
}

func appDir() string {
	log := func(err error) { optLogFatal("appDir", err) }
	currentUser, err := user.Current()
	log(err)
	homeDir := currentUser.HomeDir
	appDir := path.Join(homeDir, AppDir)
	if !goutil.PathExists(appDir) {
		createAppDir(appDir)
	}
	return appDir
}

func initializeMastodon() {
	c := readCredentials(appDir())
	mastodon.Initialize(&mastodon.Config{
		Server:       c.server,
		ClientID:     c.clientKey,
		ClientSecret: c.clientSecret,
		AccessToken:  c.accessToken,
	})
}